Europe added a record-breaking 60 GW of solar PV capacity last year, building on strong growth over the past few years. This remarkable progress is a clear win for the energy transition.

But there’s a challenge: as renewable capacity grows and electricity demand stalls—or even declines—wholesale prices are being pushed down. The impact is especially visible during solar hours, where capture price erosion is reshaping the market.

For example, in the Netherlands, negative electricity pricing occurred during 20% of daylight hours last July (2023). Similar trends are emerging across Europe, including key markets like Germany.

The result? A tougher outlook as market saturation makes standalone projects increasingly risky.

The solution? Battery Energy Storage Systems (BESS) and hybridization. Here’s how BESS is transforming solar PV:

1️⃣ Stabilizing Revenues: Batteries store excess energy during low-price hours and dispatch it when prices peak, countering price volatility.

2️⃣ Future-Proofing Assets: With PPAs harder to price and merchant risks growing, integrating BESS ensures long-term viability for solar projects. 

3️⃣ Unlocking Flexibility: Batteries enable hybridization with wind  and other renewables, maximizing output and creating diversified energy portfolios.

Solar power is the cornerstone of Europe’s clean energy future. Batteries ensure it remains sustainable, resilient, and profitable.

How do you see BESS shaping the next phase of solar growth? Let’s discuss in the comments! ⬇️

When it comes to energy storage, understanding the chain reaction behind thermal runaway is critical to mitigating its risks. As Battery Energy Storage Systems (BESS) proliferate to support renewable energy integration, the conversation around safety is louder than ever—and for good reason. Thermal runaway isn’t just an event; it’s a cascade of failures that can lead to catastrophic outcomes.

Here’s a breakdown of how thermal runaway happens and what we can do about it:

1️⃣ The Spark: Triggers That Set Thermal Runaway in Motion

• Overcharging: When a battery cell is charged beyond its voltage limits, it generates excessive heat. This causes the electrolyte to break down and release flammable gases. This over-voltage also degrades the separator, increasing the risk of short circuits.
• High Temperatures: Heat accelerates chemical reactions within cells, raising internal pressure and the likelihood of venting gases. Environmental factors—like inadequate cooling systems or extreme weather—can exacerbate the problem.
• Mechanical Damage: External impacts, like drops or compression, can deform the internal components of a cell, causing short circuits and localized heating.
• Manufacturing Defects: Imperfections during production, like microscopic debris or poor assembly, can create hotspots that serve as the starting point for thermal runaway.

Note: While prolonged undercharging can degrade a battery’s overall health and lifespan, it is not a direct trigger of thermal runaway. Undercharged batteries might be more sensitive to overcharging or overheating during subsequent recharge, but it’s not an initiating event in the same way as the others listed.

2️⃣ The Domino Effect: What Happens During Thermal Runaway

Once triggered, the cell rapidly heats up.

• Venting: The initial stage often involves the release of gases (venting) from the cell.
• Heat Propagation: The heat from the affected cell spreads to neighboring cells, raising the temperature faster than it can be dissipated.
• Self-Sustaining Reaction: It is important to note that once thermal runaway has started, it becomes extremely difficult to stop. This is because the cells contain both the fuel (flammable electrolyte) and, crucially, an oxidizer (oxygen released from the decomposing cathode material). This internal source of oxygen allows the reaction to continue even without external air, making traditional fire suppression less effective.
• Fire Risk: The released gases are often flammable, and with sufficient oxygen and an ignition source, they can ignite, creating a fire. It is important to note that fire is a potential consequence, but not a guaranteed outcome, of thermal runaway. Rapid energy discharge and failure are also possible outcomes.

3️⃣ Mitigation Strategies: Stopping the Chain Reaction Before It Starts

• Design Safeguards:
  • Voltage and Temperature Management: Implement robust battery management systems (BMS) to monitor and maintain cells within safe operating conditions.
  • Separator Innovations: Use advanced separators that resist high temperatures and reduce the likelihood of short circuits.
  • Fire-Resistant Materials: Incorporate less-flammable electrolytes (e.g., solid-state electrolytes are being developed) and coatings that can withstand thermal extremes.
• Environmental Control:
  • Optimize thermal management systems to dissipate heat evenly across the pack.
  • Include sensors to monitor humidity and environmental conditions in real-time.
• Early Detection:
  • Utilize data analytics and monitoring systems to identify signs of cell degradation or anomalies. The field of predicting thermal runaway events is still developing, and accurate prediction remains a challenge.
  • Use thermal imaging and gas sensors to detect venting gases or overheating.
• Response Systems:
  • Equip facilities with fire suppression systems specifically designed for lithium-ion battery fires, such as aerosol-based solutions or specialized water mist systems. Be aware that traditional fire suppression methods (e.g., sprinklers) may not be effective and could even worsen the situation in some cases.
  • Train teams and local emergency responders on rapid containment and evacuation protocols, including specific procedures for lithium-ion battery fires. There is ongoing research into the most effective suppression strategies for these types of fires.

The Bigger Picture

Thermal runaway doesn’t have to be a uncontrolled event. By addressing root causes and building a culture of vigilance, we can make BESS a cornerstone of a safe, sustainable energy future.

💬 What’s your perspective? How do you think we can improve industry-wide safety practices for BESS systems? Share your ideas and let’s advance the conversation. 🔋✨